1. Field of the Invention
This invention relates to tube cutters having a clamping means and wherein the saw rotates around the tube while cutting it.
2. Description of the Related Art
In the past tube cutters have had motors with saw blades in rotatable housings which rotate the saw around the outside diameter of the tube to be cut. However, little attention was paid to making precision cuts such that the tube has a square cut with no burrs, finishing marks, or other imperfections. Making precision cuts is particularly a problem with smaller diameter tubes since they bend and vibrate easily.
Clamping devices hold the tubing in place during the cutting procedure. However, in the past these clamping devices did not hold the tubes straight enough or firmly enough to keep the tubes perpendicular to the saw to ensure a square cut with no burrs, finishing marks or other imperfections. Further the clamping devices did not sufficiently dampen vibrations in the tubing to prevent vibrational movements from reducing the quality of the cut.
In the past the rotatable housing of the saws did not rotate around the tube with precision. There was not sufficient stiffness of the bearings of the rotatable housings to hold the saw blade in a plane. Further the stiffness was not sufficient to dampen vibrations in the housing, which would then transfer to the saw blade. Both of these conditions lead to a cut, which is not square, leaves finishing marks, burrs and other imperfections in the cut.
In the past centering the tube axis to the left or right with respect to the center of rotation of the blade in the rotatable housing was accomplished by moving the clamping device left or right relative the housing, but the clamping device was not sufficiently secured to the housing to hold it solidly in place and prevent movement or vibrations from detracting form the quality of the cut.
Further, in the past, the tube saws were rotated on the housing by hand thus applying uneven pressures of the saw blades on the tubes. The uneven force of the blade on the tubing promotes causes different cut rates in different portions of the tube. The uneven force on the blade promotes different vibration patterns in the tubing and in the saw blade and forces the tubing out of alignment at different amounts such that it is no longer square with respect to the blade. The differences in pressures on the blade result in different cut qualities around the circumference of the tubing. It is desired to have a uniform precision cut around the circumference of the tubing.